Pressure container



April 12, 1966 w. ROTH ETAL 3,

PRESSURE CONTAINER Filed July 2, 1964 2 Sheets-Sheet 1 INVENTOR5 willy m1 & O-Hzo SQHENK tion'and a pressure :or propellant: gas.

United States Patent 3,245,582 'PRESSURE'CONTAINER -Willy Roth, Strengelbachyand Otto Schenk, "Pratteln,

Switzerland, assiguors, by-mesneassignments,- to-Geigy Chemical Corporatiom-Ardsley, N.Y., a corporation of Delaware Filed July 2, 1964, Ser. No; 379,858 Claims priority application Switzerland,-July- 6; 1963, 8,377/63 Claims. L (Cl. 222- 4) The present invention relates to a pressure container, i.e., an aerosol container, containing an aqueous prepara If; as is usually the case, the latter consists of aliquid phase' and a gas phase and the two liquids arev immiscible, the aerosol is termed: a three-phase aerosol. .Depending upon its specific gravity, the liquefied propellent is situated above -or below the aqueous phase for spraying and the gas phase of the propellent is in everyrcase situated above the two liquid phases.

If the attempt is made to improve the spraying properties of the aqueous 'phasebyi the addition iof conventional wetting agents in order to-reduce surfacetension, varying intermixing of" the liquid'aqueous andorganic phases occurs inthe-three-phase aerosol because ofi theLIeduced surface tension and this results in undesirable foaming on actuation of the aerosolvalve. Three phase'aeros'ols containing conventional wetting agents 'are unusable because of this foaming. To prevent it, 'the' attempt has been made to separate the preparationfor spraying from the pressure gas, either by a piston or adiaphragm or some other subdivision of thercontainer interior, for example by means of a'sac. :Experiencehas shown that this step really can prevent foaming but it has the great disadvantage that spraying is no' longer satisfactory. i The pressure container according to the presentsinvention does not have this disadvantage, the container .being intended for fine spraying of an aqueous preparationfrn'ore particularly an oil-in-water-emulsion, comprising a pressuretight container which. isclosed by an 'aerosol valve iand which contains a flexible sac whichcommunicates with the valve via a 'duct 'and'which contains .the aqueous praparation for spraying, while'the'space boundedby the sac outside and the container iinside'i containsithe propellent gas. It is characterised in that the second -Jspaceis also so connectedrtothe aerosol'valve that when the latter is open both'aqueous preparation and "pressure gas escape therefrom.

sure of at least 5 atmospheres gauge. An aerosol valve 2 is inserted in the top 1a-of the container 1. The valve may, for example, be of' the typeshown in FIG. 2', in which the valve-disc is around-ring-lij forexample of tinned sheet iron or aluminium, which is secured to the container bead 5 with the interposition of a ring gasket 4 of any suitable material. The plastic or metal valve housing 6 is retained in the middle of the valve disc 3 by means of a flanged portion 7 thereof. The valve cone 8 is accommodated in the hollow valve housing 6 and may consist of a plastic material, for example a nylon, and is pressed by the coil spring 9 against the ring gasket 14 so as to close the valve. The valve cone 8 is formed with a longitudinal bore 8a with a diameter of 0.75 mm.,

3,245,582 Patented Apr. 12 1966 I for example, and atransverse bore 8b.- The press button 10 is disposed on' the valvecone 8 and'is formed-with a bore 10a communicating with the bore 8a and an aerosol jet 1000f a diameter, for example, of 0.4mm;,-communieating-with the recess 10b- The valve connect-ion or riser connection- 6b is connected to -the-base 6a*of the valve housing 6 and to it issecured the sac 11* which is in the 3 form ofa balloon of any.- flexible material,- for example a a thick-polyethylene foil or-some other material,

:elastic materials beingusedif'required. The"inside diameter of the-bore 6c in -the riser-connection 6b is-adva-nl tag'eously about 0.4 mm. to 0.65- mm.-so that its crosssectional areais about -sq; mm.- to 2 sq. mm. The 1 bore 61: together with the interior of the valve-housing 6 forms a duct which connects theinterior of the flexible sac "1'1 to' t he'aotual valve-formed by the bore 8b and the ringgasket 14. A riser16 can-be fitted over theconnection 6b-and extends'almost-td the bottom 11a ofthe. sac 11 and, if- -necessary,- Can be formed with individual transverseperforations 16a sdthateven' if the -flexible sac 11 is partially compressed the liquid 12 canalways escape. The hollow-valve housing 6 is also'formed with a lateral transverse boreor valve inlet 6d whose crosssection i's'of'about the same size as the-'cross-sect-ionof the b'ore= 6c,-i.e.,- also has a-cross-section area of sq. mm. to /3 sq. mm. This bore-6d connects the interior of :the

"valve housing 6 to the space 15- between the sac 11 and the container wall 1. This space 15-contains the-pressure or propellent .gas. In FIG. 1 .referencelSa. denotes wits liquid phase, 13b its gas phase and 12 the aqueous liquid 5 forispraying. The propellent gas may be any of the gases 1, usedin. aerosol. .technique,. advantageously." apressureliquefiable halogenated.orunhalogenated gas. or a; mixture I .of suchgases, having apressure iofiatleast 0.5 atmosphere gauge at20 C.,.for example propane, b.utane,'etc., or a f fluorine-containing. hydrocarbon,..for example dichlorodifluoromethane. .The.aqueous.prepartion..may,..for example, be an oil-in-water emulsion, for example an insecticide of the following composition:

" Percent ,Pyrethrum extract, 25% 0.8 fPipeJronylbutoxide i 1.2 y-isomer hexachlorocyclohexane 0.5 Acetone 5.0

Ethylene oxide condensation .product..with .nonyl phenol 7.5

' Water Remainder pheres gauge at 20 C.).

T The. sac 11' is..filled; tor examp1e, with .160 gof this oil-in water emulsion while the space 15 between the sac and the container wall is filled with 40 g. of a mixture of n-butane'and'iswbutane '(at a'gas pressure of 2.4-atmos- If the aerosol valve is then opened by thev press. button 10r'being pressed tin until the transverse bore 8b. is. nolonger. sealed .by'the washer 14, so that the interior of the valve housing 6 communicates with the bore 8a, the oil-imwater'emuls-ion, 1'.e., the aqueous'preparation';'fiows through'the connection 6b to the transverse bore 8b and theninto the longitudinal bo-re' 8a. At the same time .the. propellent gas-flows through the aperture 6d tothe transverse "bore "8b. 1A

first mixing occurs inside" the valve housing 6 and the gases, the active substance concentrate being made up of 85% of water and hence more favourable as regards toxicology and smell. Despite the use of combustible propellent gases the spray produced by the unit according to the invention is non-combustible, and this is a further advantage. Although numerous other aqueous preparations and the most diverse propellent gases were tried out, no danger of foaming could be found or of any other effects to disturb atomi-sation. The mixture of active substance concentrate and propellent gas given as an example hereinbefore :cannot be sprayed without the use of a sac 11, because without the use of a partition the propellent gas is emulsified into the active substance concentrate and a thick foam escapes on actuation of the valve.

Of course the flexible wall need not be in the form of a balloon or sac; any other construction is possible assuming that the two spaces separated by the flexible wall are so connected to the aerosol valve that when the latter is opened both the aqueous preparation and the propellent gas can escape therethrough. Depending on the type of aqueous preparation and the pressure of the propellent gas the flow cross-section 6c in the connection 6b and the cross-section of the lateral bore 6d will be increased or reduced. p

The sprayable mixture in the unit according to the invention may contain active substances of any type, for example pesticides, weed-killers, fungicides, b acte'ricides, pharmaceutical agents, cosmetics, domestic chemicals, etc., in either dissolved or dispersed form.

An air freshener for the aerosol according to the in vention may consist of the following:

150 g. of active substance concentrate consisting of-.-

Percent Per-fume combination 0.5

Propyleneglycol 2.5

Formaldehyde solution, 35% 0.1 Ethylene oxide condensation products with nonyl phenol 5.0

Water Remainder 50 g. of a 50-50 mixture of trichlorofiuoromethane and dichlorodifl'uoromethane.

160 g. of active substance concentrate consisting of '1 Percent Self-emulsifying wax 10 Water 90 40 g. of a mixture of n-butane and propane (with a gas pressure of 2.6 atmospheres gauge at 20 C.)

Actuation of the valve gives a fine mist which'when sprayed uniformly over a floor covering consisting of v a cloth.

cellent shine after drying. The shine given by the wax film produced with the unit according to the invention corresponds to that of the same active substance concentrate applied to the floor in the conventional way by means of It'was hitherto impossible to fine-spray wax emulsions just with water as dispersant, because without the device according to the invention the propellent gas would emulsify into the emulsion and intensive and undesirable foaming would occur at the valve.

What is claimed is:

1.5 A pressure container for fine spraying an aqueous preparation, in particular an oil-in-water emulsion, comprising a hollow pressure-tight container internally providing a compartment bounded by inner walls, aerosol valve means for closing saidpressure-tight container, a flexible'sac which remains intact and unruptured during the spraying operation disposed Within said compartment of said hollow pressure-tight container, said flexible sac containing the aqueous preparation to be sprayed and being bounded by outer walls which cooperate with the inner walls of said pressure-tight container to provide a space containing a propellant gas which is disposed externally of said flexible sac so that the pressure of the propellant gas is capable of at least partially compressing polyvinyl chloride tiles gives a wax film having an exsaid flexible sac, said aerosol valve means including a hollow valve housing connected to said sac, means providing a bore for communicating the interior of said flexible sac with said hollow valve housing in order to enable the aqueous preparation to move from said flexible sac into said hollow valve housing, said hollow valve housing incorporating means providing an inlet for movement of the propellant gas located in said space into the interior of said hollow valve housing, so that when said aerosol valve means is open both aqueous preparation and propellant gas escape therefrom, said valve inletproviding means being located externally of the intact and unruptured flexible sac.

'2. A pressure container according to claim 1, further including a riser secured to said bore-providing means, said riser extending practically to the bottom of the flexible sac.

3. A pressure container according to claim 1 wherein the cross-sectional area of said bore and said valve inlet are substantially equal.

4. A pressure container according to claim 3 wherein said cross-sectional areas of said bore and said valve inlet lie in the range of about bi square millimeter to Ms square millimeter.

5.A pressure container according to claim 1 wherein said bore-providing means and saidvalve inlet each provide an unobstructed passageway which continually communicates the interior of said flexible sac and the space for the propellant gas, respectively, with the interior of said hollow valve housing.

References Cited by the Examiner UNITED STATES PATENTS 2,689,150 9/1954 Croce 239-573 3,054,210 9/ 1962 Kratzer et al 239-573 3,080,094 3/1963 Modder'no 222-82 LOUIS J. DEMBO, Primary Examiner.

NORMAN L. STACK, AssistantExaminer. I 

1. A PRESSURE CONTAINER FOR FINE SPRAYING AN AQUEOUS PREPARATION, IN PARTICULAR AN OIL-IN-WATER EMULSION, COMPRISING A HOLLOW PRESSURE-TIGHT CONTAINER INTERNALLY PROVIDING A COMPARTMENT BOUNDED BY INNER WALLS, AEROSOL VALVE MEANS FOR CLOSING SAID PRESSURE-TIGHT CONTAINER, A FLEXIBLE SAC WHICH REMAINS INTACT AND UNRUPTURED DURING THE SPRAYING OPERATION DISPOSED WITHIN SAID COMPARTMENT OF SAID HOLLOW PRESSURE-TIGHT CONTAINER, SAID FLEXIBLE SAC CONTAINING THE AQUEOUS PREPARATION TO BE SPRAYED AND BEING BOUNDED BY OUTER WALLS WHICH COOPERATED WITH THE INNER WALLS OF SAID PRESSURE-TIGHT CONTAINER TO PROVIDE A SPACE COANTAINING A PROPELLANT GAS WHICH IS DISPOSED EXTERNALLY OF SAID FLEXIBLE SAC SO THAT THE PRESSURE OF THE PROPELLANT GAS IS CAPABLE OF AT LEAST PARTIALLY COMPRESSING SAID FLEXIBLE SAC, SAID AEROSOL VALVE MEANS INCLUDING A 